EMPLOYEE RETIREMENT PLANS - Information Relating to the Company's Plan (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017
Change in benefit obligation:
Benefit obligation, beginning of year	$ 33,176	$ 27,563
Service cost	1,301	1,214
Interest cost	1,047	1,013
Actuarial loss	8,531	2,952
Plan amendment		434
Benefit obligation, end of year	44,055	33,176
Unfunded status of the plan, end of year	44,055	33,176
Noncurrent liability	$ 44,055	$ 33,176